The MWP is very well attested in terms of archaeology, particulaly in Greenland, which really was green then, and farmed. It came to an end after the Black Death in 1351 killed one in three in Europe. This is an interesting and over-looked point by climate skeptics; fewer people meant less farming (it also led to the Modern era and the end of serfdom), less farming meant more vegetation, and forests creeping back onto lands that had been fields. Surely that suggests that there could have been an element of human involvement in the earlier rising temperatures, if man's decimation can be linked to the falling temperatures at the end of the MWP?
An earlier warm period is attested in the archaeological record by finds such as Oetzi in the Alps. We know that thousands of years ago humans inhabited the lands now covered in glaciers; as the glaciers melt, we find evidence of their lives, and this would seem to contradict the argument that the Alpine glaciers have been there since the beginning of time.
Humans have always evolved to cope with climate change. One can even argue that had it not been for climate change, then the people who became the ancient Egyptians would not have moved from the once lush savannahs turning into deserts, nor settled on the banks of the Nile, nor founded what would become our first civilization. So we owe culture, writing, history, farming, music, poetry, and a thousand other delights, ultimately to ... climate change.
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